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What is the reason behind cbegin/cend?
I wonder why cbegin and cend were introduced in C++11?
7 Answers
7
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Check if two unordered lists are equal [duplicate]
...ype for an unordered collection of (hashable) things, called a set. If you convert both lists to sets, the comparison will be unordered.
set(x) == set(y)
Documentation on set
EDIT: @mdwhatcott points out that you want to check for duplicates. set ignores these, so you need a similar data struc...
Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
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And if you want to convert all factor columns, you can use: model.matrix(~., data=iris)[,-1]
– user890739
Jan 5 '16 at 0:32
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How to get Spinner value?
... String that is displayed to the user), but not its value if you mapped an int array onto the spinner for example.
– A. Steenbergen
Feb 5 '15 at 13:58
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Remove the last three characters from a string
...ove the last three characters from the string you can use string.Substring(Int32, Int32) and give it the starting index 0 and end index three less than the string length. It will get the substring before last three characters.
myString = myString.Substring(0, myString.Length-3);
String.Substri...
Can I multiply strings in Java to repeat sequences? [duplicate]
...the rest.
Here's a sample to copy and paste:
public static String repeat(int count, String with) {
return new String(new char[count]).replace("\0", with);
}
public static String repeat(int count) {
return repeat(count, " ");
}
public static void main(String[] args) {
for (int n = 0; ...
PHP: How to generate a random, unique, alphanumeric string for use in a secret link?
...et/manual/en/function.random-bytes.php
PHP 5 (outdated)
I was just looking into how to solve this same problem, but I also want my function to create a token that can be used for password retrieval as well. This means that I need to limit the ability of the token to be guessed. Because uniqid is bas...
What's the simplest way to print a Java array?
In Java, arrays don't override toString() , so if you try to print one directly, you get the className + '@' + the hex of the hashCode of the array, as defined by Object.toString() :
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Runtime vs. Compile time
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The difference between compile time and run time is an example of what pointy-headed theorists call the phase distinction. It is one of the hardest concepts to learn, especially for people without much background in programming languages. To approach this problem, I find it helpful to ask
What...
Python JSON serialize a Decimal object
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Hmm, for me this converts Decimal objects to floats, which is not acceptable. Loss of precision when working with currency, for instance.
– Matthew Schinckel
Oct 22 '10 at 0:12
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